1. Field of the Invention
The present invention generally relates to a projection screen, and more particularly, to a projection screen suitable for a projector.
2. Description of Related Art
A projector functions based on a working principle that an optical engine is used to make an image beam projected on a plane so as to produce an optical image. Since a projection screen has good optical characteristic, a user usually makes the image beam of the projector onto the projection screen for promoting the quality of the optical image. For conveniences of using and hiding the projection screen, the reflecting curtain of the projection screen may be folded by winding on a roller on a ceiling. The image beam output from a projector has several aspect ratios (ratios of length over width) depending on an optical image, but the projection area of the projection screen has only one aspect ratio. Therefore, it is required to provide a projection screen with a plurality of aspect ratios even with arbitrary aspect ratios.